This re-creates the Kokoro equivalent crosvm/ci/build-chromeos.sh.
It is a very inefficent builder that does a fresh checkout of
chromeos for every build.
We may want to consider using some of the chromiumos recipes
for caching the repo or sdk between builds.
BUG=b:233230344
TEST=./recipes.py test run
./recipes.py run build_chromeos
Change-Id: I5d545bae4817cae5b79c5d65901081d9b1391466
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/3664842
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
